Electrode Structure, Device Comprising the Same and Method for Forming Electrode Structure

Abstract

An electrode structure comprises a semiconductor junction comprising an n-type semiconductor layer and a p-type semiconductor layer; a hole exnihilation layer on the p-type semiconductor layer; and a transparent electrode layer on the hole exnihilation layer. The electrode structure further comprises a conductive layer between the hole exnihilation layer and the transparent electrode layer. In the electrode structure, one or more of the hole exnihilation layer, the conductive layer and the transparent electrode layer may be formed by an atomic layer deposition. In the electrode structure, a transparent electrode formed of a degenerated n-type oxide semiconductor does not come in direct contact with a p-type semiconductor, and thus, annihilation or recombination of holes generated in the p-type semiconductor can be reduced, which increases the carrier generation efficiency. Further, the electric conductivity of the transparent electrode is increased by the conductive layer, which improves electrical characteristics of a device.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority from and the benefit under 35 U.S.C. §119(e) of U.S. patent application No. 61 / 146,161, filed on Jan. 21, 2009, which is incorporated by reference herein in its entirety.BACKGROUND[0002]1. Field of the Invention[0003]Embodiments relate to an electrode structure for a solar cell having a transparent electrode.[0004]2. Description of the Related Art[0005]Some thin-film type solar cells include a transparent electrode, a p-n junction and a metal film. The transparent electrode is generally made of a transparent material that allows sunlight to pass through and has excellent electric conductivity characteristics. The p-n junction is formed of a p-type semiconductor material and an n-type semiconductor material. The p-n junction may be in the form of a p-i-n junction that includes an undoped layer of intrinsic semiconductor material sandwiched between a layer of p-type semiconductor material and a layer of n-typ...

AI Technical Summary

Benefits of technology

[0013]Embodiments provide an electrode structure, device and method for increasing carrier generation efficiency by preventing hole annihilation and formation of imperfection in a thin film.

Problems solved by technology

Thee annihilation of the holes tends to lower the efficiency associated with generating current or carriers (e.g., electrons or holes) by exposing the solar cell or the display device to the sunlight.

Furthermore, a thin film obtained by CVD or PVD may have degraded physical, chemical and electrical properties due to defects, impurities, defects of crystalline structure, imperfect grain boundary, or the like.

The degraded properties is detrimental to generation and diffusion of carrier due to the sunlight, and results in poor performance associated with drift and the like.

As a result, the thin-film type solar cells generally tend to exhibit lower short circuit current and lower efficiency compared to the bulk type solar cell and are more susceptible to light induced aging.

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